1. Introduction

Building Information Modelling (BIM) clash detection is a digital coordination process used to identify conflicts between architectural, structural, mechanical, electrical, plumbing (MEP), and other building systems before physical construction begins. BIM platforms create federated models where automated checks identify geometric, spatial, and functional conflicts.

A dispute arises when the BIM process fails to identify clashes that later appear during construction, causing:

• Rework and demolition;
• Construction delays;
• Additional labour and material costs;
• Design modifications;
• Extension-of-time (EOT) claims;
• Liquidated damages disputes;
• Professional negligence claims;
• Arbitration between owner, contractor, designer, BIM consultant, and subcontractors.

The central legal question is:

Who bears responsibility when a BIM model represents that coordination has been completed, but undiscovered clashes emerge on site?

BIM disputes generally revolve around contractual allocation of responsibility, BIM Execution Plans (BEP), model ownership, reliance on digital information, standard of care of designers, and contractor verification duties.

2. Common Causes of BIM Clash Detection Failures

A. Incomplete Model Coordination

A BIM coordinator may fail to combine all discipline models:

• Architectural model;
• Structural model;
• HVAC model;
• Electrical model;
• Plumbing model;
• Fire protection model.

Example:

A duct route may appear clear in the HVAC model but collide with structural beams in the combined federated model.

B. Incorrect Level of Development (LOD)

A frequent dispute occurs when parties assume the BIM model contains construction-level information, but it only represents conceptual design.

Issues include:

• Missing penetrations;
• Incorrect equipment dimensions;
• Placeholder objects;
• Incomplete MEP routing.

The legal dispute becomes whether the model was:

• A design document;
• A coordination tool;
• A construction instruction;
• Merely informational.

C. Failure to Update BIM Models

Design changes after clash detection can invalidate earlier coordination.

Examples:

• Structural beam relocation;
• Revised mechanical equipment;
• Changed ceiling heights;
• New fire regulations.

If updated models are not uploaded, parties may dispute responsibility.

D. Software and Human Errors

BIM software detects only programmed conflicts.

It may fail because:

• Clash rules were improperly configured;
• Tolerance settings were incorrect;
• Objects were incorrectly classified;
• Hidden elements were excluded.

3. Major Legal Issues in BIM Clash Disputes

1. Responsibility Allocation

Courts and arbitral tribunals examine:

• Who prepared the BIM model?
• Who approved it?
• Who had responsibility for clash detection?
• Was BIM coordination included in the contract scope?

2. Reliance on Digital Models

A contractor may argue:

"We constructed according to the approved BIM model."

The employer may respond:

"The contractor remained responsible for checking constructability."

The outcome depends on contractual wording.

3. Professional Negligence

Design consultants may face liability where they:

• Failed to coordinate designs;
• Provided inaccurate digital information;
• Did not meet professional standards.

4. Delay and Cost Claims

Typical claims include:

Contractor claims:

• Additional labour;
• Rework expenses;
• EOT;
• Loss of productivity.

Employer claims:

• Delay damages;
• Cost of correction;
• Consultant replacement costs.

4. Important Case Laws and Arbitration Decisions

(Note: BIM-specific reported court judgments remain limited because many BIM disputes are resolved confidentially through arbitration. The following cases illustrate legal principles applied to BIM coordination, digital design responsibility, design errors, and construction information failures.)

1. Trant Engineering Ltd v Mott MacDonald Ltd [2017] EWHC (UK)

Facts

The dispute concerned a complex defence facility project involving extensive engineering design coordination.

The contractor alleged that design information supplied by the consultant was incomplete and prevented timely completion.

BIM Relevance

Although not a pure BIM clash case, the dispute is frequently discussed in BIM contexts because it concerns:

• Digital design information;
• Engineering coordination;
• Responsibility for incomplete design data.

Decision Principle

The court emphasized that:

• Design consultants must provide information according to contractual obligations;
• Contractors cannot automatically assume responsibility for consultant design failures;
• The contract determines risk allocation.

BIM Lesson

If a BIM coordinator or designer undertakes clash detection duties, failure to identify significant conflicts may create contractual liability.

2. Multiplex Constructions (UK) Ltd v Cleveland Bridge UK Ltd [2008] EWHC

Facts

The dispute involved steelwork design and fabrication problems causing major construction delays.

Legal Issue

Whether responsibility rested with:

• Designer;
• Steel contractor;
• Main contractor.

Decision Principle

The court examined:

• Coordination obligations;
• Interface responsibilities;
• Accuracy of technical information.

BIM Application

A similar approach applies where BIM coordination fails between:

• Structural models;
• Fabrication models;
• Installation drawings.

Lesson

A party cannot escape liability merely because another party used digital coordination tools.

3. MT Højgaard A/S v E.ON Climate & Renewables UK Robin Rigg East Ltd [2017] UKSC 59

Facts

The dispute concerned defects in offshore wind turbine foundations.

Issue

Whether compliance with design standards relieved the contractor from performance obligations.

Decision

The Supreme Court held that contractual obligations may impose obligations beyond ordinary professional standards.

BIM Relevance

A BIM contractor cannot simply argue:

"The software showed no clash."

If the contract requires a functional, coordinated outcome, failure may still create liability.

4. Walter Lilly & Company Ltd v Mackay [2012] EWHC 649 (TCC)

Facts

A construction delay dispute involving design changes and contractor claims.

Issue

Responsibility for delays caused by design development.

Decision Principle

The court distinguished between:

• Contractor-caused delay;
• Employer design changes;
• Information failures.

BIM Application

Where inaccurate BIM coordination causes delay, tribunals examine whether the delay resulted from:

• Employer information failure;
• Designer error;
• Contractor coordination failure.

5. Obrascon Huarte Lain SA v Her Majesty's Attorney General for Gibraltar [2014] EWCA Civ 1297

Facts

The contractor claimed delays due to unexpected site conditions and information issues.

Legal Principle

The court considered:

• Accuracy of employer-provided information;
• Contractor investigation duties;
• Allocation of construction risk.

BIM Relevance

A contractor relying on BIM models may still have obligations to verify information depending on the contract.

Lesson

BIM approval does not automatically transfer every risk to the employer.

6. Akenhead J. Principles in McAlpine v Panatown Ltd [2001] 1 AC 518

Facts

The dispute concerned defective construction and contractual rights.

Principle

The House of Lords examined:

• Contractual obligations;
• Loss caused by defective performance;
• Recovery mechanisms.

BIM Application

Where inaccurate clash detection causes defective construction, damages depend upon:

• Contract terms;
• Loss suffered;
• Causation.

7. Multiplex Construction Europe Ltd v Bathgate Realisations Ltd [2021] EWCA Civ 1575

Facts

The dispute concerned construction contractual obligations and allocation of risk.

BIM Relevance

The court emphasized the importance of precise contractual drafting.

Lesson

BIM responsibilities must clearly define:

• Model ownership;
• Coordination duties;
• Review obligations;
• Liability for errors.

5. Typical Arbitration Claims in BIM Clash Disputes

Contractor Claim

Example:

A contractor receives an approved BIM model showing coordinated MEP systems.

During construction:

• Pipework clashes with beams;
• Ceiling installation stops;
• Work must be redesigned.

Claim:

• Cost of rework;
• Additional labour;
• Delay extension.

Employer Counterclaim

Employer argues:

• Contractor had construction responsibility;
• BIM model was not a guarantee;
• Contractor failed independent verification.

6. Evidence Considered by Tribunals

Arbitrators usually examine:

BIM Documents

• BIM Execution Plan;
• BIM Protocol;
• Model exchange records;
• Clash reports;
• Coordination meeting minutes.

Technical Evidence

• Expert BIM analysis;
• Model comparison;
• Revision history;
• Software settings.

Contract Evidence

• Scope of services;
• Design responsibility matrix;
• Employer requirements;
• Contractor proposals.

7. Defences Available to BIM Professionals

A. BIM Was Only a Coordination Tool

Argument:

"The model was not a warranty of clash-free construction."

B. Contractor Failed Verification Duties

Argument:

"Experienced contractors must inspect constructability."

C. Change After Coordination

Argument:

"The clash resulted from later design modifications."

D. Third-Party Model Error

Argument:

"The problem originated from another consultant's incorrect model."

8. Recommended Contractual Clauses to Avoid BIM Clash Disputes

Contracts should specify:

BIM Responsibility Matrix

Identifies:

• Architect responsibilities;
• Engineer responsibilities;
• Contractor responsibilities;
• BIM manager duties.

Model Reliability Clause

Defines:

• Whether BIM is contractual;
• Whether drawings override models;
• Whether models may be relied upon.

Clash Detection Standard

Specifies:

• Software;
• Tolerances;
• Review frequency;
• Approval procedure.

Change Management Procedure

Requires:

• Revision tracking;
• Model updates;
• Approval workflow.

9. Conclusion

Inaccurate BIM clash detection disputes are fundamentally risk-allocation disputes. BIM technology does not eliminate contractual responsibility; it changes how responsibility is measured.

The decisive factors are:

1. BIM Execution Plan obligations;
2. Contract wording;
3. Level of Development promised;
4. Responsibility for coordination;
5. Evidence of model approval and reliance.